The present invention relates to a wall element (central or lateral) presenting a body to which stationary pins carrying idly mounted rollers are snap-connected. The element, together with other equal or similar elements, is intended to form central or lateral walls bounding conveying paths for products in general, for example containers (such as bottles, cans, etc.), or their accumulation stations. In the case of central walls, the element presents two parallel rows of idle rollers; in the case of lateral walls, the element presents only one row of idle rollers.
The load-bearing structural part of the known elements is formed from a single moulded piece of plastic material either strong in itself or strengthened by suitable fillers. This structural part comprises an upper and lower base elements and a core which connects them together. In the case of elements for central walls, the cross-section of the load-bearing structural part has an I-shaped configuration, whereas for lateral walls the configuration is C-shaped.
For snap-fitting the roller pins, the lower and upper base elements are provided laterally with seats, of number equal to the number of pins, into which these latter are snap-fitted. The accompanying FIG. 1, relative to a known solution, shows on an enlarged scale a detailed perspective view of a seat and the end of the relative pin. The roller pin 1 is cylindrical, with its end 1a also cylindrical, but of lesser diameter. The load-bearing structural part is in this figure represented by its lower base element 2 (of which only the part concerned is shown), where it presents a tapered lateral lead-in 2a opening into a circular seat of diameter equal to or slightly less than that of the end 1a of the pin. The narrowest (blocking) part 2c of the lead-in 2a is narrower than that of the end of the pin 1, so that the pin can be snap-inserted into the seat 2b with a certain force, by utilizing the elastic deformability of the materials. The pins with the relative rollers are hence adequately retained in the load-bearing structural part of the element.
The known solution can however be improved in the sense of reducing the overall size, the weight and the constructional complexity of the structural part of the element, by eliminating the core joining the lower and upper base elements of the wall element, and using the pins themselves to join the upper and lower base elements so that these become independent parts, i.e. not forming an integral piece.